Rotary pump



Patentqd May 31, 1921.

ROTARY PUMP.

APPLICATION man ocr. 6. A1920.

G. B. PETSCHE.

XxW-mm in communication with the admission cham- GUSTAV B. PETSCHE, 0FYONKERS, NI'QW YORK.

ROTARY Application led Uctober 6,

vreference being had to the accompanying drawings, which form a partthereof. y My invention relates to rotary pumps of the type in which thepiston consists ofan eccentric ring having an extension which forms apartition between the admission andF delivery ports of the cylinder andis articulated to a rotary slide moving in a segmental cylindricalbearing. The object of my in`v vention is primarlly to provide such arotary pump or compressor with a grid slideY valveopening to permit theflow of the compressed gas into the delivery chamber and closedpositively and accurately at the end of the delivery cycle of the pistonby contact with the piston extension. Further objects of my inventionare to provide means for actuating the slide valve so that it will openrapidly and completely at the proper point, and to provide incombination with the devices for regulating the movements of thedelivery valve a valve moving with or forming apart of the slide towhich the piston is articulated, for closing the admisslon port duringthe period when the piston is out of contact with the periphery of thecylinder. The nature of my improvements will be best understood asdescribed in connection with the drawings in which they are illustratedand in wlnch- Figure l is a side elevation of a compressor embodyin myinvention taken as on the line 1-1 of ig. 2, and

Fig. 2 is a front view of a twin cylinder compressor partly shown insection on the line 2 2 of Fig. 1 n A, A', indicate two cylinders formedin a single casting and provided with face plates A2 and A3. Bis thecylindrical internal periphery of the cylinder A interrupted asindicated at B', B2, to give clearances to the piston extension. C isthe segmental cylindrical bearing for the slide havin formed in it, vasshown, an admission port ber E. E is a passage leading from the deliveryside of the compressor-.to the reeeiving chamber E", F 1s the drivlngShaft Specication of Letters Patent. l Batentd May 31,1921.

1920. serial No. 415,146

of the compressor havingv secured to it eccentrics as indicated at F onwhich are vseated the eccentric ring pistons G having the extensions .Gfarticulated at their ends as lndlcated at T to a rock lever I, I',pivoted.

at H and having formed o r attached to it the slide J and practicallyforming apart of this slide is the admission valve' M, the slide beingshown recessed between the p0rtions J and AM as indicated at J and there cessed portion lying in communication with the admission chamberthrough the port d. This construction is for the purpose-of preventingthe building up of pressure on the portion of the slide cut away asindicated at J. O is a valve bushing inserted inthe passage' E andhaving formed in it the grid valve seat indicated at Of. P is a gridvvalve working on this seat and formed, as shown, with a' valve stem P'to which is secured a piston Q and a plunger Q. P2 1s an extension ofthe valve stem through a bushel passagein the wall of the compressorlying in the path traversed by the piston extension G at the completionof lits compressing cycle. R is the cylinder in which the piston Qworks, the ends of the cylinder beingR connected by ports indicated atR' and -2 and through an adjustable restrict- 'ing plug R3, 4S is acylinder in which works the plunger Q and, as shown, this cylinder isconnected by al pipel S with a port S2 formed through the wall B on thedelivery side of the compressor.

In operation the gas tok be compressed enters from the chamber D throughthe port D and after thel piston G has come in contact with the wall ofthe cylinder at B is compressed, the pressure gradually building upuntil the pressure in the in the receiver chamber The port S2 is locatedat such aV point that the pressure building up in the cylinder istransmitted through the pipeS to the cylinder S and acting against theplunger Q this pressure will, when the pressures above and below thevalve are equal, move it rapidly in a direction to open it, smoothnessof motion being insured by the dash pot eli'ect of the cylinder P andiston P. After the valve is opened the en of the rod P2 projects intothe cylinder so that, as the piston completes its compression cycle andimmediately before it ylinder equals that At this point also theadmission valve M closes the port D so that as the piston moves from itspoint of contact at B2 to its point of contact at B the admission valveis closed and any compressed gas contained 'in the clearance spaces,while it may How back into this cylinder of the compressor, cannotescape backward into the admission chamber. lt is, of course, obviousthat after the piston has passed over the port S2 pressure is releasedin the cylinder S so that there is no pressure on piston S tending tooppose the action of the extension Gr closing the valve.

Having now described my invention, what l claim as new and desire tosecure by Letters ratent, is:

1. llna rotary compressor having an eccentric ring piston provided withan extension forming a partition between the admission and deliveryportsl of the compressor cylinder, a valve for closing the delivery portand a valve actuating rod extending into the compressor chamber when thevalve is open, at a point lying in the path ot the piston extensionduring the completion of a compression cycle or' the piston and so as tobe acuated thereby to close the valve.

2. ln a rotary compressor having an eccen.- tric ring piston providedwith an extension forming a partition between the admission and deliveryports of the compressor cylinder, a valve for closing the delivery port,a piston and cylinder or opening the valve, a conduit leading from saidcylinder to a point in the compressor chamber traversed by the pistonnear the end of its compres-r sion cycle, and a valve actuating rodextending into the compression chamberwhen. the valve is open, at apoint lying in the path of the piston extension during the completion ofa compression cycle of the piston and so as to be actuated thereby toclose the valve.

3.' ln a rotary compressor having an eccentric ring piston provided withan extension forming a partition between the admission livery port, a

v valve.

masonry and delivery ports ot the compressor cylinder, a grid slidevalve for closing the depiston and .cylinder for ope ing the valve, aconduit leading from said cylinder to a point in the compressor chambertraversed by the piston near the end oit its compression cycle and avalve actuating rod extending into the compression chamber when thevalve is open at a point lying in the path of the piston extensionduring the completion ot' a compression cycle of the piston and so as tobe actuat thereby to close the having a cylin.-

der and slide bearing formed in its casting, a rotary eccentric ringpiston provided with an extension partition and an oscillating slide towhich said extension is articulated, the combination therewith of anadmission port termed through the -slide bearing, a valve extension otthe slide operating to close'said port in the interval between theoperative cycles of the piston, a delivery port, a delivery valve andmeans for positively closing said valve actuated by the piston'extensionat the end cycle.,

5. ln a rotary compressor having a. cylinder and slide bearing Jformedin its casing, a rotary eccentric ring piston provided with an extensionpartition and an. oscillating slide to which said extension isarticulated, the'combination therewith of an admission port formedthrough the slide bearing, a valve extension ot the slide operating toclose said port in. the interval between the operative cycles of thepiston, a delivery port, a grid slide valve for closing said port, acylinder and a piston for opening said valve said cylinder beingconnected to the compressor cylinder at a point traversed by the pistonnear the end of its compression cycle, and means for closing said valvelying in the pathof and operated by the piston extension at the end otthe compression cycle,

' kGrlUS'llrV B, PETSCHE.

t. ln a rotary compressor of each compressionlili

